Physical constant, sometimes called fundamental physical constant or universal constant, is a physical quantity that is generally believed to be both universal in nature and have constant value in time. It is contrasted with a mathematical constant, which has a fixed numerical value, but does not directly involve any physical measurement.

There are many physical constants in science, some of the most widely recognized being the speed of light in vacuum c, the gravitational constant G, Planck’s constant h, the electric constant ε0, and the elementary charge e. Physical constants can take many dimensional forms: the speed-of-light signifies a maximum speed for any object and is expressed dimensionally as length divided by time; while the fine-structure constant α, which characterizes the strength of the electromagnetic interaction, is dimensionless. — Wikipedia

Researchers and engineers at the Spallation Neutron Source (SNS) are making progress on the construction of VENUS, the facility's newest instrument for studying materials in exciting new ways that are currently not possible for open research programs in the United States.

The sun is the brightest object in the sky and has been studied for hundreds of years, but it continues to hide some secrets. The visible sun is extremely hot, at a temperature of about 5500 degrees. Surprisingly, on top of this sits a layer of gas, called the corona, which has a temperature of almost 2 million degrees, over 300 times hotter than the actual surface of the sun. What heats up the corona to 2 million degrees has been an enduring mystery with no satisfactory answer.

The Quantum Hall effect (QHE) is one of the most important discoveries in physical sciences. Due to the one-dimensional (1-D) dissipationless edge states, QHE exhibits exotic transport properties with quantized Hall resistance of h/νe2 and vanishing longitudinal resistance. Here, h is Planck's constant, ν is Landau filling factor and e is electron charge. QHE usually originates from the formation of remarkable energy gap and the broken time-reversal-symmetry, which requires materials with […]